Change this statement to 1) "most AV receivers are built within the same standards and perform predictably, and well, with other equipment, and 2) most high-end amplifiers vary unpredictably from any known output/input compatibility standards, cannot be expected to work well with other audio equipment or be accompanied by any documentation of the requirements for matching them to other equipment, but when carefully, intuitively, matched to other high end equipment, by the user, can produce excellence beyond standards."
...and I think you're getting close to the positions that have actually been taken in these discussions. It's a whacky audio world you live in, micro. One in which the engineering seems to have gotten a good start, at best, when the equipment is shipped. Then the real work, the experienced audiophile's work of system-buiding, with no guidance, no map from the manufacturer to follow. He's left with trial, error, and his ears and experience to find the source A that optimizes preamp B to optimize amp C to drive speakers D to performance heights that even the component designers couldn't imagine...or at least couldn't be bothered to tell you how to achieve.
You are, by far, the most important link in the chain! More critical to ultimate system performance than the designers of mere pieces of the puzzle! You're almost up their with the artists themselves, turning mere reproduction into music.
Thing is, I don't believe it. I believe there are a few, a very few, high-end designers/manufacturers putting out equipment that truly dances to it's own, non-standard music and requires very careful choices to achieve compatibility. I believe most of them are plug-and-play compatible with other equipment built to industry input and output standards. I believe they don't give you detailed instructions for matching their amps to sources, pres and speakers because they know it is unnecessary, and that the extreme members of the synergy crowd believe it is necessary because it elevates their importance in the process and gives them something to fiddle with.
Tim